Colored couplers containing solubilizing groups



United States Patent 1 2,725,292 COLORED COUPLERS CONTAINING SOLUBILIZING GROUPS Bruce Graham, Los Altos, Calif., and Paul W. Vittum and Arnold Weissberger, Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application May 15, 1952, Serial No. 288,022. 6 Claims. (Cl. 95-6) This invention relates to color photography and particularly to colored couplers for use in photographic processes. 7

Color-forming compounds which react with the development product of aromatic amino developing agents to form colored images upon photographic development are well known. Generally, these color-forming compounds of couplers are colorless or substantially colorless. This lack of color is usually desirable where the coupler is to be incorporated in the emulsion layer and the unused coupler remains after formation of the colored image. When the coupler is used in the developing solution, it may be colored without detriment to the final image and certain colored couplers have been used in this way.

Couplers which are in themselves moreor less strongly colored, and which contain a chromophore group which is split oil or destroyed during and by means of the coupling reaction, with the result that the original color of the coupler is destroyed and a new dye is formed upon coupling, are disclosed in Glass, Vittum and Weissberger U. S. Patents 2,453,661; 2,455,169; 2,455,170 and 2,521,-

If the colored couplers are to be used in aqueous colloidal emulsion carriers, the couplers must also contain groups conferring water solubility such as sulfonic acid or carboxylic acid groups. These lyophilic groups may be present in the coupler portion of the molecule or the phenylazo portion of the molecule or both. Compounds containing lyophilic groups have been described in our prior application Serial No. 260,098, filed December 5, 1951, now Patent No. 2,657,134.

We have now found that a difierent type of solubilizing group may be used in colored couplers to accomplish useful results in color photography. The new colored couplers which are the subject of the present invention contain an azo portion in which the solubilizing group is separated from the aryla'zo unit by a connecting chain of such constitution that it can release electrons toward the arylazo unit and thus facilitate the coupling function. These compounds may be represented by the following general formula:

ice

2 in which A is an aryl group, B is an electron releasing substituent on A, and C is a solubilizing, lyophilic group. More specifically, our invention involves the use of coupler compounds having the formula NlElO 0Q l sHu uHu CHiOOOH 1-phenyl-3-{3-[2 1 (2,4di-tert-amylphenoxy) (2 -sulfobenzam1do)benzamido] benzamido}- 4 [4 (carboxymethoxy) phenylazo] -5-pyrazolone SIO3H N=o-Ni'rco NHOOO i Q CuHrN NEGO- N C NH C O C tsHsN CO- H H16 0 0H 1-pheny1=3-{3-[2 (2,4 di-tert-amylphenoxy2) 5 ('2 -sulfobenzamido) benzamido] benzamido}- 4- [4 (car oxymethyl) phenylazo1-5-pyrazolone SOaH CHEC' 0 0H tert-amylphenoxy) a 5 (3 sul o enzamidoWenzaxhlddlphnethy1}-2-naphthamide (4) 'I SOIH on NBC o ONH(CHa)zC -NHG 0Q fi sH1i N H 0 on l-lg dgroxy 4 [4 -(cargoxygmethl%pheny 1 4 156( 4:53 U. S. Patent 2,322,027. When used in this way they are emgiffiini fifiil gfl o enzaml 0) enza 1 on) incorporated in a solvent which is then dispersed in the 0o-I H N=N CH:COOH -(t-t q y pg fy)ng y l-izf l -(tt r -buty ghenoxy) emulsion and it is generally desirable that all of the Rfl 0] I cal oxyme y )1) my pylazm acid groups be-esterified. However, in certain cases, a

C H free acid group may be present in the molecule when the couplers are lncorporated in this way, if there are suificient CONE C solvent-solubihzmg groups 111 the molecule as in the case of compound No. 5.

' b02055 In order to facilitate crystallization of the couplers it is often convenient to prepare the carboxylic acids in N=N the form of their esters and the sulfonic acids in the form of their sulfonyl chlorides. If the compounds are to be incorporated directly in the gelatin, these groups can then be hydrolyzed just before the couplers are added to the emulsion. The preparation of our compounds will now be demo 0 on scribed. 1 hydr0xy 3, cgrbethoxy 4 [4 (carboxymethynppenylazo] 4. The parent colorless couplers (without the arylazo (2, 4-di-tert-amy1phenoxy)-2-naphtham11de group) are known compounds or are prepared as follows. Y i CH3 N==o NHoobH0--o.m-t

l oon N=NCH:SOaH

1-[4 (4tert-buty1phenoxy)phenyl]-3-[ -(4-tert-buty1phen propionamido]-4-[sulfomethybphe ylazo]-5-pyrazolon% g ggi fi 3 g g g fi g (8) s|03H Example 4. a D Compounds 3 and 4 are described in U. S. application F Q Serial No. 260,098, now U. s. Patent 2,657,134, Ex- CpH NHCO ample 1.

CO- H Compounds 5 and 7 are described in U. S. Patent 2,369,489, Example 47.

Parent compound No. 6 was prepared as follows:

I T=N 0 H 2-(2,4-di-tert-amylphenoxy) 5 nitrobenzoyl chloride 5 was converted to the ethyl ester, M. P. 40-45 C., by

Q i refluxing it in ethyl alcohol. This was reduced to the p 5 amino derivative by use of 10% palladium on carbon in 5H petroleum ether at room temperature. The amino com- CHZSOBH pound was condensed with l-hydroxy-Z-naphthoate at 2335i;niisltifijtfgalfitt will?titll i tiis fititt to yield i a l- -py a ol e 'di-tert-amylphenoxy)J-Z-naphthamhde, M. P. 152-153". The couplers of our invention are miscible with aqueous T anilines usefl in the Preparatlon of the diaFo colloid emulsion carriers such as gelatin or polyvinyl alcof' for F Wlth Wuplers are efislly hol and can therefore be incorporated directly into the obtamed- P'AmmP h eny1acet1c and 1s commerclauy usual photographic emulsions. When incorporated d available. Other anilines were prepared as follows: rectly in this way the couplers are used in the form of pf y -P- Y acid Was their water soluble salt. They may also be used in the ma y the action of P-nitrobenzyl Chloride on Sodium ester form in processes such as those of Mannes and 'bisulfite in the presence of sodium hydroxide. The re Godowsky U. S. Patent 2,304,940 and Jelley and Vittum duction was accomplished by dissolving the p-nitrobenzylsulf onic acid in cold concentrated ammonium hydroxide and passing in hydrogen sulfide. The salt of the desired aniline was obtained by concentration of the reaction mixture.

p Aminophenoxyacetic acid.p Nitrophenoxyacetic acid [1. Am/Chem Soc., 39,2424 (1917)] was reduced in aqueous solution over 5% palladium on carbon. The free amine was converted to the hydrochloride for storage. M. P. 222-223" C. The esters of these acids can be easily prepared by the conventional methods.

The final colored couplers were prepared in general by dissolving the appropriate colorless coupler in pyridine at C. and treating the resulting solution withthediazotized aniline derivative at 0? C. The resulting dye was isolated by drowning the reaction mixture in cold, dilute hydrochloric acid. The products were washed in cold water on a filter. The following specific method for the preparation of compound No. 1 is typical:

Example 1 A solution of 83 parts of colorless coupler No. 1 in 300 parts of pyridine was cooled to 0 C. and treated with a cold solution of p-carboxymethoxybenzenediazonium chloride prepared as follows: p-aminophenoxyacetic acid hydrochloride (21 parts) in 250 parts of water and 13 parts of concentrated hydrochloric acid was cooled to 0 C. and treated with a solution of 7.3 parts of sodium nitrite in 30 parts of water. The aqueous pyridine dye solution was allowed to stand overnight. It was then poured into a mixture of 500 parts of concentrated hydrochloric acid in 1000 parts of ice. The product was collected and washed repeatedly with cold water on the filter. It was then triturated with water, and collected and washed again. Yield 88 parts of orange dye which sinters above 150 C. and melts to a spongy mass at about 170 C.

The physical properties of the amorphous colored cou plers are listed below:

M. P. Compound 1 Amorphous softens ISO-170 C. Compound 2 Softens 160-190". Compound 3 Sinters 180", M. 205-210. Compound 4 Sinters 190, M. ca. 205. Compound 5 Sinters 140. Compound 6 250-255. Compound 7 M. 273 (from acetic acid). Compound 8 Sinters 200", M. 250-260.

Our couplers are intended to be incorporated in one of the emulsion layers of a multilayer coating in order to secure the masking eifects described in Hanson U. S. Patent 2,449,966. The Hanson process involves a color correction method in which a colored coupler is incorporated in the photographic emulsion layer prior to exposure and upon development is converted to a colored image where the layer is exposed. The coupler remaining in the unexposed portions of the layer retains its original color and by suitable choice of the color of the original coupler and the color of the final dye image, a masking or correction effect can be obtained.

The following example illustrates the incorporation of one of our couplers directly in a gelatino-silver halide emulsion:

Example 2 A S-gram sample of the coupler having the structure of compound 3 was wet with ml. of ethyl alcohol and heated with 5 ml. of sodium hydroxide solution. The addition of 200 ml. of water produced a clear solution which remained clear when the pH was reduced to 6.5-7.0. The neutralized solution was mixed with about 250 ml. of a silver halide emulsion and coated according to standard practice. An exposure on this material after normal negative processing gave a negative cyan image and an orange-yellow positive image.

The following example illustrates the incorporation of one of our couplers in a'solvent dispersion in a gelatinosilver halide emulsion.

Example 3 A solution of seven grams of the compound 5 was prepared by heating with 25 ml. of dibutylphthalate at 165 C. A dispersion of this solution was prepared by milling with ml. of 10% aqueous gelatin solution and 20 ml. of 5% Alkanol B at 45 C. This dispersion was mixed with ml. of water and approximately 250 ml. of a silver halide emulsion and then coated according to standard. practice. Exposed coatings of this material when processed in the usual negative color development process gave a negative magenta image and a positive yellow image.

Various photographic developing agents can be employed with'the' couplers of our invention. The primary aromatic amino developing agents are generally suitable including the phenylene-diamines and aminophenols. The alkyl phenylenediamines may be substituted in the amino group as wellas in the ring. Suitable compounds are diethyl paraphenylenediamine, monomethyl paraphenylenediamine, dimethyl paraphenylenediamine and para-aminophenol. These compounds are usually employed in the salt form, such as the hydrochloride or the sulphate which are more stable than the free amines. All of these compounds have a primary amino group which enables'the'oxidation product of the developer to couple with the color-forming compounds to form dye images.

The following developing solution is suitable for developing gelatino-silver halide layers containing colored couplers according to our invention incorporated either directly in the emulsion or in solvent dispersion:

Grams 2-amino-5-diethyl-amino toluene HCl 2 Sodium sulphite 2 Sodium carbonate 20 Potassium bromide 2 Water to 1 liter.

Where we refer in the claims to pyrazolone, phenol and naphthol rings, it is to be understood that we intend to include substituted as well as unsubstituted rings, as well known in the art and as illustrated by the specific examples above.

It will be understood that the examples and modifications set forth herein are illustrative only and that our invention is to be taken as limited only by the scope of the appended claims.

We claim:

1. A silver halide emulsion containing a coupler compound having the formula:

where R represents the atoms necessary to complete a ring selected from the class consisting of pyrazolone, phenol and naphthol, C represents the carbon atom in the 4- position of said ring, X is selected from the class consisting of -O and a single chemical bond para to the azo group, and Z is selected from the class consisting of -COOH and --SO3H and their water-soluble salts and alkyl esters.

2. A silver halide emulsion containing a coupler compound having the formula:

where R is a mononuclear aryl radical.

3. A silver halidc emulsion containing a coupler compound having the formula:

' C ONE-R wherc'R is an aralkylradical. v I

"4. A silver halide emulsion containing a couplercompound having't-he formula:

N C NHC OR R is an aryloxyalkyl radical and R is a-monou j ry ad V i I 5. A s il v e1: -h a1ide emulsion containing'a coupler compound having the formula:

whre R and R are mononuclararyl radians.

U silver ha lidc emulsion containing a coupler combound Having fife formula ;N-= C-NHO O R Microismn arj ldiq alkyl railica'l and R is a mono- "nuclear'afyl radical.

-10 s V 7 a *Refrhc'es Cifeflin the filc" of'-th' ispatcnt UNITED STATES "PATENTS 2,455,169 mass-ss-ss sss s s sss Nov. 30, 1948 15 FOR El' GN PKTENTS js 93,1 1 74 "ciatfn'rfitain Feb. 1'12, .1943 595,657 Great Britain 'jFeb. -24, 1948 627,814 Great Britain Aug. '16, 1949 20 267,707 Swi'tz'fland Apr. '1, 1950 

1. A SILVER HALIDE EMULSION CONTAINING A COUPLER COMPOUND HAVING THE FORMULA: 